Part of the process of working on my summer project of building a rock retaining wall involved excavating suitable rocks out of the hillside back behind our house with my tractor and backhoe. The rocks were mixed in with the dirt in the hillside. They often came out quite easily but sometimes when they were tightly packed together, they needed some persuasion. A lot of the more stubborn rocks were marked with scratches from the backhoe teeth but this one struck me as particularly interesting due to how straight the lines were and that they were at nearly a right angle to one another. Unlike the others with quite random marks, it looks like a purposefully created geoglyph.